Los Angeles -LRB- CNN -RRB- -- `` We are One '' ? Not quite .

Singer Jennifer Lopez , who was supposed to perform the official song of this year 's World Cup at the opening ceremony this week , has pulled out .

`` Regretfully Jennifer Lopez will not be attending this year 's World Cup opening ceremonies , '' her rep told CNN in a statement late Sunday night .

No reason was offered .

Lopez teamed up with rapper Pitbull and Brazilian star Claudia Leitte to record Brazil 2014 's official song , `` We Are One -LRB- Ola Ola -RRB- . ''

The trio was slated to perform at the tournament 's opening ceremony ahead of the host 's first match with Croatia on Sao Paulo on Thursday .

The World Cup song has been a tradition since the 1966 World Cup in England , when a song dedicated to the tournament mascot , a lion named `` World Cup Willie , '' was released .

Four years ago , it was Shakira telling the world to `` Waka Waka '' ahead of South Africa 2010 .

Soon after the song was released , Pitbull , who has previously worked with the likes of Christina Aguilera and Enrique Iglesias , spoke of his joy at being involved in the project .

`` I 'm honored to join Jennifer Lopez and Claudia Leitte at the FIFA World Cup to bring the world together , '' said Pitbull . `` I truly believe that this great game and the power of music will help unify us , because we are best when we are one . ''

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Singer pulls out of opening ceremony performance

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She recorded `` We are One -LRB- Ola Ola -RRB- '' with Pitbull and Claudia Leitte

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No reason was given for her withdrawal